So when you're not helping someone move, make sure the spare tire's one of the heaviest things you have in the back.

Four: Smooth it out. Accelerating and braking unnecessarily is a downer on your gas tank!

Keep a steady speed as much as possible. Use cruise control when it makes sense.

Got brakes? Use 'em only to slow down. Resting your foot on the pedal can ruin everything.

Five: Shut it off. Don't be idle about idling. Your car's burning gas whenever it's running, so if you're sitting for more than 30 seconds, power down. That can keep your costs down and your wallet and your gas tank, filled up.